Proportional letter-feeding and adjunct features



Oct. 11, 1960 SUNG-CHING ..|N s 2,955,695

we AND ADJUNCT FEATURES PROPORTIONAL LETTER-FEEDI Filed Oct. 27, 1958 4 Sheets-Sheet 1 Q I h\\\\\\\\\\\ I INVENTOR -CHl/VG LING 'ATTORNEY sums-cn-ufic; LIN 2,955,695

Oct. 11, 1960 Y PROPORTIONAL. LETTER-FEEDING ANDADJUNCT FEATURES Filed Oct. 27, 1958 4 sheets-sheet 2 INVENTOR su/vacm/va u/va ATTORNEY suus-cums LING. 2,955,695

PROFQRTIONAL LETTER-FEEDING AND ADJUNCT FEATURES Oct. 11, 1960 r 4 Sheets-Sheet :5

Filed 00% 27, 1958 Oct. 11, 1960 SUNG-CHING LING PROPORTIONAL LETTER-FEEDING AND ADJUNCT FEATURES Filed Oct. 27, 1958 4 Sheets-Sheet 4 ow om ON 9 82089 35 0v on ON 9 0% 0m ON 9 Qv 0m ON 9 United S2. ties ,rate d io 11,1960

PROPORTHDNAL LETTER-FEEDING AND ADJUN CT FEATURES Sung-Citing Ling, Farmington, com, assignor to Underwood Corporation, New York, N.Y., a corporation of This invention relates to typewriters embodying letterfeeding devices which responsive to, character-selective operations produce letterfeeding steps which generally are proportional in width to the individual characters that are being typed.

It is an over-all object of the invention to provide a typewriter of the above capability which is efficient and simple to handle by the operator, is further capable of operation at high speeds equivalent substantially to typewriters producing uniform letter feeds, and moreover is manufacturable and serviceable at very low cost.

It is a more particular object of the invention to provide in association with a proportional spacing type writer having a step measuring dog which normally is in control of the typewriter carriage, a mechanism of utmost simplicity whereby said dog is differentially controlled automatically at each typing operation to take differentially a new toothhold in an escapement wheel, thereafter to govern, the carriage reliably and efliciently to execute and advance generally proportional to the character which is being typed.

A further object of the invention is to provide in connection with a typewriter having capability of three different space yields, a reliably operative space controlling mechanism which comprises a single, differentially positionable space selecting device which advantageously has a normal position determining a most frequently required size of space and capable of being given two other positions by the typing mechanism respectively in connection with operations thereof calling for one or another diiferent size spaces. r

It is another object of the invention to provide in association with a proportional spacing mechanism, a device which in a simple and efiicient manner is preconditionable to several states so that in each of said states an operation of a single space key will cause the. proportional spacing mechanism to yield a different size of space. p

In conjunction with the foregoing object it is a still further object to provide in association with said space: key controlled mechanism, an eflicient power device to reduce greatly the effort which otherwise would be required to operate said space key.

Still other objects and features of the invention will be apparent upon consideration of the detailed description which follows, as the description is read in the light of the accompanying drawings.

Figure 1 is a right-hand sectional side view-through the middle of an 'all' electric Underwood typewriter wherein the proportional letter-feed mechanism of the invention and related mechanisms have been incorporated. a

Figure 2 is a left-hand' front perspective view of a space bar and an associated escapement rocking mechanism. 7

Figure 3 is a front perspective view in a rightward direction of a type action-governed space regulating ,2, v mechanism along with a device which is predeterminedly settab le for regulatingword spaces. 7

Figure 4 is a left-hand side .view of the settable' word space regulating device also seen in Figure 3.

Figure-5 is a fragmentary front view illustrating in conjunction with type action sublevers a space controlling mechanism which is laterally displaceable under case shift control to diflferently condition it.

Figure a bottom elevation of the escapement proper of the invention a step measuring escapement dog being in a normal, carriage-holding position.

Figure 7 is a fragmentary bottom view showing the escapement of Figure 6 rocked from normal position and its step' measuring dog spring mo'ved against a space controlling slide or member occupying in such figure a nQrmaL'tWo-units control position.

Figure 8 is a fragmentary-bottom view of the escapement showing the space controlling slide or member of Figure 7 moved to a one-unit control position, but the stepmeasuring dogis still holding the escapement wheel in its old'feed position.

Figure 9 is similar to Figure 8 but the step measuring dogis shown to havetaken up a feed controlling position against the space controlling; slide standing in its one-unit control position. I

, Figure10 is similar to Figu're8 but the space controlling slide or member is in a three-units control'position.

Figure 11 is similar to Figure9 but the step measuring dog is shown to haveassumed under control of the space controlling slide a three-units control position.

Figure 1 2 is anoperationalchart representing typing operations efiected in overlapping successions and representing in connection therewith the orderly and reliable functioning .ofthe space controlling slide for the step measuring dogas wellas the' orderly and reliable func tioning of said step measuring dog itself.

Figure 13' illustrates the step measuring dog in the process of paying out a three-units feed while, due to a newly started .typingoperat'ion, the space controlling slide or member already being moved from its three-unit to its one-unit control position.

I Figurej 14 is a righbha'nd sectional view showing the escapement. in normalj condition.

Figure 15 is'a'schematic view of the step measuring dog in the process of beingi'remeshed with the escape ment wheelteeth, and p Figure 16 is a schematic view looking down obliquely on a type bar gliidewhichQ is provided with graduations.

j, Old typewriter mechanism Refe'rringnow more particularly to Figure l, the invention applied to an all-electric Underwood typewriter which embodies a power typing mechanism of the kind shown in the patent to Yaeger, No. 2,254,764, dated September 2, 1941. Said typing mechanism includes many type bars 10 pivotally carried in a usual segment 10a, and individually swingable against a platen 11 to type at a common typing point. Each typebar 10 is power'operable byan actuator 12. through a train of mechanism comprising an actuator supporting arm 16 and a" generally upright sublever 13, there being a transverse row of actuators"12, arms'16 and sublevers 13. All of said actuators 12 are normally spring-held clear above a toothedpo'wer "roll 14 'and are adapted. to be lowered'into' toothedgmotion-receiving"relation with said roll, the said roll 14 rotating constantly in the direction.

of .the arrow when themachine'is in use. Key levers 15, one for every actuator 12,;are' individually operable to connect the actuators '12 selectively with the power roll 14 forsingle transitoryioperations, thereby to efiect selectiveoperations of the-type bars 10 against said platen V 11. Springs 17, 18 and 20 bias the parts of the described type actions toward their normal positions shown in Figure 1. The stated arms 16 and sublevers 13 are in a usual mannerpivoted on common pivot rods 21 and 22, respectively, which in turn are carried on usual bars 21a and 22a which have, transverse slots therein for said arms and sublevers.

The segment 10a is supported on a case-shiftable frame indicated at 19 and is downwardly case-.shiftabl'e therewith in a usual manner from the lower'caseposition seen in Figure 1 to an upper case position. The framework of the machine comprises a trackway 30 whereon a carriage 23 is guided for travel, said carriage having turnably supported thereon the said platen 11. For carriage guiding cooperation in the trackway, 30, the carriage includes a channel bar 24,.therebeing. usual antifriction elements 25 provided between the traekway and. said channel bar.

The carriage 23 is constantly urged in letter-feed direction, that is leftwardly, by a spring motor which is indicated at 2 6 and has a drawband connection 27 with the carriage. However, letter-feeding movement ofthe carriage is subject to the control of the proportional escapement of the invention which will presentlyibe described.

Proportional escapement mechanism 7 This mechanism is of adesign adapted to feed the carriage one definite feed unit or two, or three multiples thereof. For example, when certain very narrow characters, such as i and PIare typed, the carriage feeds a single feed unit. Typing of letters of average width will produce carriage feeds amounting to the two units, while a few wide lower case characters and most upper case characters will produce a three-units carriage feed.

Such escapement mechanism comprises. in association with an escapement wheel 28 which has geared connection with said carriage 23, a step measuring escapement dog 31. This dog, as seen'in Figure 6, holds the escapement wheel in such figure against clockwise, carriage advancing movement, the dog having a, hole therein affording an abutment 32 for normal contact with a stop pin 29. The escapementwheel 28 is fast on the lower end of a shaft 33, which, at its upper end has a gear pinion 34 fast thereon. The shaft 33 is rotatably supported in an upper and a, lower bearing respectively indicated at 35, and 36 in Figure 1 A, rack 37' supported on and extending lengthwise of the carriage 23. is normally in mesh with said pinionv 34. and thereby provides the stated geared connection. of: the escapement wheel with the carriage. Said rack 37, in amannernot shown, is mounted to allow its movement 'transversely of the carriage out of mesh with-the pinion 34, thereby to facilitate quick relocations of the carriage. The teeth on the escapement wheel 28 are! provided thereon in agreement with the units in the terms of which the escapement steps are to be effected. The step measuring dog 31 has pivotal support on a. large-headed stud 38 provided on a dog rocker 40. Pointed pintles 39 supported on an escapement bracket 43 extend oppositely into spaced, bent ends 41 and 42v of said rocker so that the latter is rockable to swingthe dog}31,o ut of and into mesh with the teeth ofgthe escapement wheel 28.

The position of the rocker-is normally upwardly swung so that the escapement dog 31 is in mesh with the teeth of the escapement wheel as: seenin Figures 1 and 14. Therefore due to the carriage beinggul'g d in letter-feed direction the dog 31 normally standsrnoved rightwardly in Figure 6 to the limit ofsthe stop,.pin -.29.v Ineach typing operation as an imprint is being; effected the: dog rocker is imparted a.slight counterclockwise; movement respective to Figure 1 to clear the'dog;31 from' the; escapement wheel teeth. To, this, end eaeh: type barr.10,- by a heel 4-5 imparts nearthe, end of1itsoperatingstroke toward the platen, a rearward, motion; tqpa conventional arcuateuniversal bar 46. ,Thelatteryissconnwi da 7 to a member 48 which is pivotally carried at 52 upon spaced arms 53 of the case shift frame 19. A downreaching arm 54 of the swingable member has an adjustable link connection 55 with an upreaching arm 56 of the dog rocker 40. Springs 57 and 58 bias the dog rocker and the member 48 to their normal positions seen in Figure 1.

Each time the rocker 40 is operated to swing the step measuring dog 31 downwardly out of carriage holding engagement with the escapement wheel 28, such dog swings on its pivot stud 38 under the urge of a spring 60 clockwise of Figure 6 in order to take up any one of three specific relations in respect to the teeth of the still quiescent escapement wheel. The escapement dog 31 has two teeth designated S and L for cooperation with the escapement wheel teeth. Each step measured out in its limited movement by the escapement dog 31 to the escapement wheel is concluded by the dog tooth 5. Such dog tooth may thus be regarded to be a stop tooth. On the other hand the tooth L has the purpose to lead the stop tooth S as will become evident later herein into spaced-controlling mesh with the escapement wheel 28 in connection with triple-units feeds. The said dog 31 swings immediately and rapidly because its mass is very small. On the other hand, the carriage having stood still and its mass being substantial, it will advance only after its inertia has been overcome. While thus the carriage and the escapement wheel stand momentarily still, the step measuring dog snaps counter to the feed direction, namely clockwise of Figure 6.

The particular relation which the step measuring dog will take up relative to the escapement wheel is regulated automatically in deference of the magnitude of the letter feed required in connection with each particular typing operation. Thereafter as a further incident related to each typing operation, the rocker 40 restores so that the step measuring dog then will become remeshed with the escapement wheel but in a different tooth relation therewith. Meanwhile the inertia of the carriage is being overcome and the escapement wheel will then advance under the control of the escapement dog 31 the number of feed units as predetermined by the etfected remeshing relation.

For the purpose of controlling the movement of the step measuring dog 31 clockwise of Figure 6 into the required new tooth relations with the escapement wheel 28, there is provided a member 61 which under type key control will have any one of three space controlling positions at the time the dog 31 rocks free of the escapement wheel. The said member 61 is shown in the form of a space controlling stop slide which for convenience may be carried on the dog rocker 40. Said slide 61 has a long rear edge 62 in sliding contact with a lip 63 of a dog-rocker supported plate 64. Additionally, a slot 65 in said slide 61 provided parallel to said edge 62 has a shouldered screw 66 associated therewith and fast on the dog rocker 40. In this manner said stop slide 61 is capable of guided movement parallel of said edge. If incidental to a typing operation a normal control position of said slide 61 prevails as in Figure 6, then in such operation said dog 31 is rocked free of the escapement wheel 28 and will snap clockwise from the Figure 6 to the Figure 7 position, a nose 67 on the dog being limitedly striking a stop face 2 on said slide 61. From Figure 7 it will be perceived that when there after the dog rocker 4t) restores, the escapement wheel 28 is adapted to execute a two-tooth advance under control of the escapement dog, which in turn means a two-units advance of the carriage.

In Figure 8 the space controlling slide 61 has been moved substantially leftwardly to its rightward limit such figure and when the dog 31 becomes rocked clear of the escapement wheel it will snap clockwise to engage a stop face 1 on the slide as illustrated in Figure 9. This predetermines a single unit escapement movement to take place following the restoration of the dog rocker I 40 -as the carriage then moves. Movement of the slide to a position intermediate that of Figures 6 and 8, see Figure 10, places a notch 3n in the slide 61 into registration with the swinging path of the dog nose 67, so that as the dog 31 becomes rocked clear of the escapement wheel, it will unobstructed by the slide snap clockwise to the position shown in Figure 11, wherein a stop face 3 afforded by the stated hole in the dog contacts the pin 29. The dog is. then in a position so that when the rocker restores it will be picked up by the escapement wheel through the lead-in tooth L and thereupon the tooth S will restrict the escapement wheel to a three-units carriage advancing movement. It is to be understood that the bottomof the notch itself could constitute the limit for the last stated spring urged motion of the dog 31.

A rockable structure 71, see Figure 3, is adapted to be operated by certain type-selective operations of the typewriter, by some such operations to move the stated stop slide 61 a maximum to its one-unit-selective position of Figure 8 and by some other of-such operations to move the said stop slide a lesser extent to the three-unitselective position of Figure 11. In connection with many of the type selective operations of the typewriter, the said slide 61 will have the normal two-unit-selective position seen in Figure 6. The said rockable structure 71 comprises a shaft 72 by which it is pivotally, as well as endwise slidably carried in two spacedbracket plates 73.

Said plates are preferably accommodated in slots cut transversely into the pivot rod supporting bars 21a and 22a (as seen in Figure 1), the pivot bars 21 and 22 being used to lock the plates in place. At its right end the said shaft 72 has an arm 74 which by a link 75 is communicative with a horizontal bell crank 76 having a wire link connection 77 with the stop slide 61. Said bell crank has pivotal support at 78 upon a bracket structure 80 which is borne on a crossbar 81 of the machine framework. The connected train of parts is under the constant restoring influence of a spring 82 associated with the bell crank 76. Thus the position seen in Figure 3 prevails normally, wherein the stop slide 61 stands restored to the limit of the screw 66 for the stop face 2 to stand selected, ready to be contacted by the dog ear 67. A frame supported stop pin 83 may be provided in association with the arm 74 of the rockable structure 71 to establish adefinite normal position therefor. Said rockable structure 71 comprises on its shaft 72, at irregular locations therealong, a series of downreaching arms 84. In reference to Figure 3, it will be seen that certain of these arms 84 have laterally projecting pins which normally lie along a forwardly bowed dot-anddash line 91 and that certain of these arms have pins which lie more forwardly disposed along another forwardly bowed dot-and-dash line 93. Two of the arms 84 have one pin along said line 91 as well as another along said line 93. The rightward digits of the linedefining numerals 91 and 93 signify that the arm supported pins lying respectively therealohg are for selecting one and three units control positions of the slide 61. The stated pins are variously identified by either a small character or a capital character, or both, each such character signifying the particular character typing operation or operations in which a related typeaction sublever 13 is adapted to be operative thereon to effect a predetermined-extent of operation of the rockable structure 71, this becoming evident later herein. The type action sublevers 13 reach from their pivot rod 21 to graded extents upwardly for connection to the related type bars, and, relatedly the progressively more centrally located sublevers 13 have greater angular movement, all in a usual manner. The stated pins on the arms 84 are provided along forwardly bowed lines 91 and 93 in order that the said pins lying on each said lines will respectively receive equal extent displacements from the sublevers 13, the more centrally located pins being picked up with increasingly greater motion loss. The said projecting pins on. the arms 84 constitute faces, whereby certain of the type action sublevers 13 are adapted to operate the rocking structure 71 as required.

Endwise displacement of the rocking structure 71 is effected under the control of the case-shift body 19. To this endtits shaft 72 has fast on its left end an annularly grooved collar 94. A bell crank 95 having a pin 96 extending into the groove of said collar 94 has pivotal support at 97 on an ear of the plate 73. Said bell crank 95 is operable by thecase-shift body or frame 19 through a link 98 having a pivotal connection withthe left-hand one of the two usual studs 100 by which the conventional type bar rest 101 is supported. A case shift of the body 19 downwardly to upper case position will swing the bell crank clockwise of Figure 3 and will give the rocking structure 71 a slightly rightwardly displaced position. A case shift upwardly to lowercase position will effect the restoration of the rocking structure leftwardly to the Figure 3 position. In the lower case position of the case-shift body 19, see Figures 3 and 5, only those ofthe pins on the arms 84 which have by lowercase character designations applied thereto are in alignment for operation by their related type action sublevers 13. When the rockable structure71, consequential to an upper case shift, stands rightwardly moved, then only such of the pins of the arms 84 which have capital character designations applied thereto are in alignment for operation by their related sublevers 13. Some of the pins which have one capital as well as one small character designation and are long enough to be acted on by a related type action sublever 13 in either endwise position of the rocker structure 71, that is they are adapted to be operated in either case position.

From the above itwill be seen that dependent on the particular type action which is operated and further dependent on the case shift position of the type bar segment 10a, the structure 71 may be rocked fully, or partly, or not at all. Consequently the stop slide 61may occupy any one of the three stated positions when a type bar in its operation approaches the platen. the escapement dog rocker 40 at the end of each type bar operation toward theplaten becomes operated by the universal bar 46, the escapement dog'will instantly snap to the particular carriage feed predetermining position governed by the differential position stop slide 61. This happens before the carriage will be set in motion under the influence of the spring motor 26. When any type bar recedes from the platen after effecting an imprint, the resultant spring urged restoration of the dog rocker 40 will remesh the escapement dog 31 with the escapement wheel'in-the appropriate tooth relation so that the carriage will then under the control of the dog,

. step feed an appropriate number of feed units suited to the particular character that was typed.

I -Iaving reference to Figure 15 it will be noted that the teeth of the escapement wheel 28 are rounded at their trailing sides as'shown in Figure 15. Furthermore, the

trailing edges of the dog teeth S and L are beveled as away from the rocker 40. From Figure 14 it will be seen that between the dog 31 and the head of its pivot stud 38 therefor, there is interposed alight compression spring 106. This spring has the tendency to maintain the dog3'1 upwardly in flat contact against rocker 40 but permits a temporarylag in the upward, engaging movement of the dog 31' if either of its teeth S or L Therefore, when '7 clash with the teeth of the escapement wheel when the dog rocker 40 is being restored. The dog rocker 40 additionally to the step measuring dog 31 carries pivotally thereon, as at 107, another dog 108 which comes into play temporarily to yield control over the carriage each time the dog 31 is rocked clear of the escapement wheel. Said dog 108 has ordinarily the position on the dog rocker seen in Figure 6, except during carriage returns and tabulations, as later herein will be explained. Namely, it stands limitedly counterclockwise urged by a spring 110 which is arranged intermediate the dog 31 and a stud on the dog 108.

The provision of the dog 108 additionally to the dog 31 assures that the carriage is at all times under definite control. Also if in a rather unusual manner a threeunits feed step has not come fully to the conclusion while a new escapement rocking operation already follows, then the dog 108 is instrumental to hold the carriage temporarily while the step measuring dog 31 takes up its appropriate differential position for measuring a feed step.

Because of the arms 84 of the rockable structure 71 are fast on a shaft 72 which provides the axis of rotation therefor, and are outreaching therefrom, their weight can be held to a minimum to constitute with such shaft a relatively small rockable mass which for all practical purposes has no detrimental strength-of-imprint affecting influence on the type actions. Due to the said relatively small mass, the said spring 82 can moreover be of very light strength and the rocking structure with associated mechanism will function in a most lively and responsive manner, reliably at high typing speeds.

The single rockable structure 71 whereby the space controlling stop member or slide 61 is differentially controlled by the typing operations to exercise in turn differential control over the space measuring dog 31, makes feasible a proportional escapement mechanism of very low cost and of utmost operational efficiency and reliability. Also it makes feasible a mechanism which is very rugged and easily serviceable.

The specific arrangement of the stop faces 1 and 2 on the stop member 61 With the three-units controlling notch 3n therebetween, makes possible the correct and reliable positioning of said member at extremely high typing speeds. The reasons and advantages for said specific arrangement will now be brought out in detail. It is of course necessary that the control slide or member 61 in every typing operation become early enough positioned to exercise early enough the required control over the step measuring dog 31. Obviously no particular timing problem exists when in association with a typing operation the control slide 61 is required'to be in its normal position. This is because it will. take up such position relatively early as an incident to the preceding typing operation. Almost all lower case characters require a two-units feed and inasmuch as most typing is done in lower case characters, it has been conceived to arrange the face 2 of the stop slide 61 so that it will stand positioned in the restored position of said slide. According to the illustrated preferred embodiment of the invention, any typing operation calling for a three-units feed of the carriage imparts the partial movement to the slide 61 which will position its notch 311 into the path of the dog nose 67. One advantage of this is that if a two-units feed is required to follow next, the said dog nose 67 will move very early in the homing movement of the dog 31 toward its normal position sufficiently to allow restoration of the slide 61. Such would not be the case if a projecting one-unit control face were between a two-units stop face and a three-units control notch, as obviously this would require a near homing of the dog 31 by the feed movement of the carriage before the stop slide could take up its normal twounits control position. Furthermore in the featured construction, if in two rapidly successive typingoperatio nsa 1 I one-unit feed controlling position of the slide is required to follow a three-units position, then, as illustrated in Figure 13, the operating movement of the slide 61 to the one-unit control position is in the same general direction as the movement of the dog nose incident to the homing movement of the dog 31 carried out consequential to the closely previous typing operation calling for a threeunits feed. Therefore, if in the operation of the slide 61 the leading edge of its stop face 1 should catch up with the dog nose 67, as may be visualized from Figure 13, then such leading edge will act on the dog nose 67 to swing the dog toward home position, ahead of the feed step being executed by the escapement wheel.

If now reference is had to Figure 12, it will be seen that the type bar operations are represented therein to start at 50 millisecond intervals. This is about double the mean rate at which a speed typist typewrites. Of course a typist will often type two letters in faster succession but 50 milliseconds is a safe allotment for closely successive typing strokes. In said Figure 12 the typing strokes are shown to overlap by about 20 milliseconds but actually could overlap a few additional milliseconds. In the first represented type bar operation in said Figure 12, it is shown that a three-units control operation of the rockable structure 71 and connected stop slide 61 begins after about 14 milliseconds of type bar operation. The step measuring dog 31 moves clear of the escapement wheel 28 at 28 milliseconds and immediately snaps to the appropriate three-units control position to become positioned thereat at 35 milliseconds. At 36 milliseconds the dog rocker 40 reengages the step measuring dog 31 and at such time the carriage feed spring 26 just about overcomes the inertia of the carriage, wherefore the latter will execute its three-units feed movement under control of the dog 31. Such movement is complete after 40 m lliseconds. A second typing stroke is represented to begin at 50 milliseconds after the first typing stroke, while the stop slide 61 is still restoring toward normal position. Said second typing stroke is shown to require a one-unit feed of the carriage. The movement of the stop slide 61 in such stroke is shown to become reversed to operating di- 'rection at 2 milliseconds. This time the operation is for a maximum movement, so that at 28 milliseconds the stop face 1 is fully selected. The three-units feed step of the carriage in the first represented typing stroke ends at about 26 milliseconds of the second typing stroke. At 36 milliseconds of said second typing stroke the carriage starts to execute its required one-unit movement which consumes only about 20 milliseconds. The third represented typing stroke calls again for a threeunits feed of the carriage and is started while the oneunit 'feed movement of the carriage resultant from the second typing operation is still under way and while the coding slide 61 has only moved partially toward normal position. At 17 milliseconds of this third instituted typing operation the coding is still restoring as an incident of the second typing operation and is at such time picked up to move to its required three-units control position. Such position of the slide 61 is fully attained at 28 milliseconds when the feed dog 31 rocks clear of the escapement wheel. Between 28 and 35 milliseconds in this third typing stroke the escapement dog moves to its control position for governing a three-units feed. At 36 milliseconds in this last typing stroke the carriage starts its three-units feed which is of 40 milliseconds duration. The fourth graphically represented typing operation calls for a two-units feed. At 28 milliseconds in such stroke 2 the escapement dog 31 moves free of the escapement wheel and of course long before the control slide 61 'has restored to its normal two-units control position. The two-units feed of the carriage then starts at about 36 milliseconds and ends at 19 milliseconds. Said schematic view illustratesthat the escapement of the'invention is always reliably controlled and that the carriage comes to a full halt intermediate successive typing operations to allow the escapement dog 31 to take up each time its appropriate feed determining position.

Movement of the rockable structure 71 need not. be uniformly accurate. Slight under or overtravel of the control slide 61 beyond its three-units selective position is tolerable without any ill effects.

The machine of the invention includes a conventional carriage tabulating mechanism disclosed in the patent to Helmond, No. 2,301,878, dated December 1, 1942. Some parts of this tabulating mechanism are shown in Figure 1 and new mechanism is provided whereby for the required duration of each tabulation the escapement mechanism of the invention becomes automatically released to provide for tabulating advance for the carriage. The carriage 23 has on a bar 115 a usual row of keysettable tabulating stops 116 spaced at double feed increments. Normally withdrawn below said stops 116 there is a usual tabulator counterstop blade 117, a spring 118 having a downward and rightward urge on the upper portion of said counterstop blade. A ledge 120 on the counterstop blade 117 provides that the latter will be detained upon its projection into tabulation terminating relation with any set stops 116 until such a stop moves 'said blade leftwardly.

The projection of the counterstop blade 117 is eflected in response to the operation of a tabulator key 117a, by callinginto operation in a manner not shown, an actuator 119 similar to the type action actuators 12. Said actuator 119, through alink 121 will rock a usual pivoted structure 122 which by a link 123 has connection with a blade lifting bell crank 124. The stated pivoted structure 122 has an arm 125 from which a link 126 is up-reaching to act on a stud 125 provided on an arm portion of the escapement rocker 40. Therefore, the dog 31 is rocked downwardly clear of the escapement wheel'28 incidental to each instituted tabulation. Concomitantly, the holding dog 108 moves downwardly into the plane of the escapement wheel. However, through a bell crank 127 controlled by the bell crank 124 the said dog 1118 is automatically swung clear of the escapement wheel teeth. Therefore incident to each projection of the tabulator blade 117. theescap'ement wheel is rendered free of the dogs 31 and 108 and will allow tabulating travel of the carriage. As the tabulator counter-stop blade 117 at the end of the carriage tabulating run is displaced, said blade 117 will immediately drop to its normal position and therebywill place the dog 31 again in control over the carriage. It is to be understood that the control slide 61 resides at such time in its two-units control position so that then a little less than a two-units advance of the carriage follows.

The escapement rocker 40 is controlled by the carriage return mechanism to move the step measuring dog 31 clear of the escapement wheel 28 for the durations of all effected returns. To this end a part 128 which has connection with the carriage return clutch controlling mechanism of the Underwood all-electric machine will control a draw link 130 to impart an upward movement to said pin 129 of said rocker 40 incidental to each carriage return clutch closing operation. 'Said draw link 1130 becomes restored incidental to each clutch opening operation of the carriage return mechanism so that at settable mechanism includes a finger piece 136 on a vertically adjustable sliding member 137. Said member 137 is afforded slidable support on two frame supported pins 133 situated in slots 140 of the member. A spring urged detent pawl 141, by cooperation with notches 142 inthe slide, is adapted to detent the slide in any one of three positions to which it may be moved. Said finger piece 136, see Figure 3, has a pointer for registration with indices representing-space magnitudes in feed units.

Responsive to each operation of the space key 135, see Figure 2, its supporting lever 143, by, acting over a lever 144 operates a lever 145 to. engage a power actuator I 146 with the toothed power roll 14 and thereby will cause it to execute a power stroke. A spring urged re-. storing movement follows when in the power stroke a tooth 147 of the actuator rides into engagement with the toothed roll 14. The front .end of the actuator 146 is supported on a pivoted arm 148 and is adapted to operate a lever 1511 forwardly. On said lever 150 there is carried at 151 pivotally an arm 152 and is urged by a spring 153 forwardly thereon against an anchorage pin 154 for said spring 153. Said arm 152 has a stud 155 reaching laterally into a vertically dispose-d slot 156 of an arm 157 which has pivotal support on a stud 158 projecting from an ear on the slide 137. A lower, forwardly reaching portion of the arm 157 has two stepped shoulders 161, 163. The operating stroke of the arm 152 is limited by an eccentrically adjustable bolt 165, see Figure 4, and permits, by the yielding of spring 153, the operation of the lever 150 to be carried on a little further. The leftmost one of the arms 84 of the rockable structure 71 has a pin 164 reaching leftwardly through a clearance hole in the adjacent bracket plate 73, into a plane in which the arm 157 lies. If the finger piece is set as in Figure 3 pointing to the indice 2, the lever 150 will actuate the am 157 in a low arc, clearing the pin 164, so that the rocking structure 71 will remain quiescent and the space controlling slide 61 "will accordingly stand in its twounits control position. If the finger piece 136 is adjusted to the indice 3,- the arm 157 in being actuated by the lever 150 will swing in a slightly higher are and by its shoulder 163 will impart a short movement to the pin 164 so that the rockable structure 71 will position the space controlling slide 61 in the three-units control position. If the finger piece 136 is set to register with the indice 1, the operation of the arm 157 causes a maximum movement of the rocker 71, because the shoulder 161 will contact the pin 164. In such case the'control slide 61 will be moved to its one-unit control position. The operation of the actuator 148 is extended beyond the point at which said arm 157 reaches its limit of operation as gaged by thebolt 165. It is then that an arm 168 (Figure 2) by motion derived from the actuator 146 will cammingly act on a roller 170' carried on the dog rocker 40, thereby to actuate the latter, The said arm 168 is part of a bail structure which includes a shaft 171 and another arm 172. The latter, by a link 173 is connected for operation to the actuator 146. The operation of the bail starts early in the power stroke of the actuator 146, but the cam arm 168 acts on the rocker 40 only after the arm 152 has moved to its limit. Said actuator 146 restores immediately, the dog rocker being rocked only long enough for the dog 31 to snap to the proper feed controlling position determined by the selected position of the slide 61. When then the dog rocker restores, the dog 31 will measure out. to the escapement wheel a feed step of the units value predetermined by the setting of the finger piece 136.

The mechanism just described is advantageously employed to spread or contract the spacing of words or individual characters. It is very advantageously employed especially for-the typing of justified lines. If employed forthis purpose, the line is typed with an appropriate number of space key operations made while the finger piece 136 has one particular setting and then with the finger piece given another setting the line is completed. The mechanism has the advantage that no repeated at- 11 tention must be given to operate the proper one of several space keys.

A type bar guide of usual construction is indicated in Figure 16 at 175. Graduations 176 thereon, spaced in accord with the feed units, aid the operator in properly locating the carriage in connection with making corrections. For example, if in making a correction, a letter m is to be typed next to an i, the carriage is first located to place the letter i just leftwardly of the longer graduation 176, about midway between such longer graduation and the leftwardly adjacent shorter graduation. If then m is typed it will be properly spaced to the letter i. Substantially the same procedure is used in making corrections involving other characters. The graduations on both type bar guide portions may be used to aid in locating the carriage for typing character in sertions.

Variations may be resorted to within the scope of the invention, and portions of improvements may be used without others.

What is claimed is:

.1. In a typewriter comprising pairs of related types consisting each of a lower-case and an upper-case type, a letter-feed carriage, means constantly urging said carriage in letter-feed direction, a case-shift mechanism adapted to occupy a lower or an upper case position, elements individually related to single pairs of said types, arranged in a row and individually operable generally transversely of such row and means operable by each of said elements to cause a typing impression by its related lower or upper case type, depending on whether the caseshift mechanism occupies its lower or its upper case position, the combination with an escapement wheel which is capable of rotation by the carriage in a carriage-advance direction, of an escapement dog normally in engagement with said wheel, a stop against which said dog is normally engaged through carriage-advance rotation of said wheel, means operated automatically responsive to the operation of any of said elements to disengage said dog transitorily from said escapement Wheel, spring means to move said dog upon its disengagement in a direction from said stop, counter to the said carriage-advance direction of rotation of said wheel, and means to regulate the movements of said dog from said stop for governing subsequently its reengagement to occur in different feed determining tooth relations with said escapement wheel, comprising a roekable structure generally co-extensive with said row of elements and having a pivot axis generally parallel thereto, means controlled by said case-shift mechanism to position said roekable stru"- ture axially in one or another of two positions, said rockable structure having variously arranged faces thereon whereby in each of its axial positions specific ones of said elements are adapted to operate it to a short extent and certain other specific ones of said elements are adapted to operate it to a greater extent, some of said elements adapted to operate said roekable structure in either of its axial positions and certain others only in one, and a single member controlled by said roekable structure so that in the unoperated and the greater extent operated position of said roekable structure there are presented respectively stop faces to said dog which will limit its movement from said stop to predetermine respectively a double and a single-tooth advance of said escapement wheel, said member having a notch between said step faces which responsive to said short extent operation of said roekable structure becomes positioned to allow a maximum movement of said dog away from said stop to predetermine a triple-tooth advance of said escapement wheel.

2. In a typewriter comprising pairs of related types consisting each of a lower-case and an upper-case type,

a letter-feed carriage, means constantly urging said carriage in letter-feed direction, a case-shift mechanism adapted to occupy a lower or an upper case position,

elements individually related to single pairs of said types, arranged in a row and individually operable generally transversely of such row and means operable by each of said elements to cause a typing impression by its related lower or upper case type, depending on whether the caseshift mechanism occupies its lower or its upper case position, the combination with an escapement wheel which is capable of rotation by the carriage in a carriageadvance direction, of a pivoted escapement dog, normally in engagement with said wheel, a stop against which said dog is normally engaged through carriage-advance rotation of said wheel, means operated incidental to the operation of any of said elements to disengage said dog transitorily from said escapement wheel, spring means to swing said dog away from said stop upon its disengagement from said escapement wheel, and means to regulate the movements of said dog from said stop for governing subsequently its reengagement to occur in ditferent feed determining tooth relations with said escapement wheel, comprising a roekable structure generally coextensive with said row of elements and having a pivot axis generally parallel thereto, means controlled by said caseshift mechanism to position said roekable structure axially in one or another of two positions, said roekable structure having variously arranged faces thereon whereby in each of its axial positions specific ones of said elements are adapted to operate it to a short extent and certain other specific ones of said elements are adapted to operate it to a greater extent, some of said elements adapted to operate said roekable structure in either of its axial positions and certain others only in one, said dog saving a nose leading in the pivotal direction in which the dog is movable from said stop, and a single member operable by said roekable structure counter to the direction in which said nose swings when said dog swings from said stop, said member in the unoperated and the greaterextent operated position of said roekable structure presenting respectively stop faces to said dog nose which will limit movement of said dog from said stop to predetermine respectively a double and a single-tooth advance of the escapement wheel, said member having a notch between said two stop faces which responsive to such short extent operation of said roekable structure becomes positioned relative to said nose to allow a maximum movement of said dog away from said step to predetermine a triple-tooth advance of said escapement wheel.

3. In a typewriter comprising a system of types, a letter-feed carriage, means constantly urging said carriage in letter-feed direction, elements arranged in a row and individually operable generally transversely of such row, and means operable by each of said elements to cause a typing impression by a related type, the combination with an escapement wheel which is capable of rotation by the carriage in a carriage-advance direction, of an escapement dog, a stop against which said dog is normally engaged through carriage-advance rotation of said wheel, means operated automatically responsive to the operation of any of said elements to disengage said dog transitorily from said escapement wheel, spring means to move said dog upon its disengagement in a direction from said stop, counter to the said carriage-advance direction of rotation of said wheel, and means to regulate the movements of said dog from said stop for governing subsequently its reengagement to occur in different feed determining tooth relations with said escapement wheel, comprising a roekable structure generally coextensive with said row of elements, having a pivot axis generally parallel thereto, and having variously arranged faces thereon whereby specific ones of said elements are adapted to operate it to a short extent and certain other specific ones of said elements are adapted to operate it to a greater extent, and a single member controlled by said roekable structure so that in the unoperated and the greater extent operated position of saidv roekable structure there from said stop to predetermine a triple-tooth advance of said escapement wheel.

4. In combination with a typewriter having a carriage,

a case-shift mechanism adapted to occupy a lower and i an upper case position, a series of elements arranged in a row and selectively operable transversely of'such row to cause various upper case and lower case character typing operations depending on the positions given to said case-shift mechanism, and a proportional feed escapement conditionable to yield feeds of three different magnitures; a rockable structure generally coextensive with said row of elements and having a pivot axis generally parallel thereto, means controlled by said caseshift mechanism to position said rockable structure axially in one or another of two positions, said rockable. structure having variously arranged faces thereon whereby in each of its axial positions specific ones of said elements are adapted to operate it to one position and certain'other specific ones of said elements are adapted to operate it a greater extent to another position, some of said elements adapted to operate said rockable structure in either of its axial positions, certain others only in one, selective positioning of said rocking means in any one of three positions being thus effected at operations of said elements, a carriage spacing key, a manual control settable to any one of three positions, means conditionable by the different settings given to said manual control to predeterminefor such means different paths of operations, mechanism responsive tosaid carriage spacing key to operate said differentially conditionable means in its predetermined path, means controlled by the different-path operations of said conditionable mean to cause selective positioning of said rockable structure in said three positions, means governed by the selective positioning of the rockable structure to precondition said escapement for yield of any one of three different magnitudes of feed, and means responsive to the terminal part of operation of any one of said elements and responsive also to said carriage space key after the said mechanism has acted, to cause said escapement mechanism to yield the particular magnitude of carriage feed for which it becomes preconditioned.

5. In combination with a typewriter having a letter: feeding carriage; an escapement controllable for yield of carriage spaces of different magnitudes, a carriage spacing key, a manual control settable to, diflerent positions representative of carriage spaces of different magnitudes, means conditioned by the different settings given to said manual control to render such means operable in dif: ferent paths, mechanism responsive to said carriage spacing key to operate said means in the particular path for which it is conditioned by said manual control, and means to control said escapement mechanism by the operation of said means in said different paths to yield carriage spaces of different magnitudes.

I 6. In combination with a typewriter having a letterfeeding carriage; an escapement mechanism conditionable for yield of carriage spaces of different unit values and operable to yield the carriage space for which it is conditioned, a spacing key, a manual control settable to different positions representative of carriage spaces of different unit values, a cyclic power actuator adapted to be called into operation by said spacing key, means differentially conditionable by said manual control and operable by said cyclic power actuator in a first part phase of its operation to render said escapement mechanism conditioned for yield of that unit value space for which said manual control i set, and means operable by said cyclic power actuator in a later part phase of its operation to operate said escapement.

mechanism to condition it for carriage feeds of different magnitudes, said means including a member which is operable from a normal position to a plurality of different operated positions and which in each of said positions at operation of said escapement mechanism is adapted to control it to yield a different magnitude of carriage feed, a spacing key, a manual control settable to different positions representative of at least some of the carriage feeds for which the escapement mechanism is conditionable, a cyclic power actuator adapted to be called into operation by said spacing key, means differentially conditionable by said manual control and operable by said cyclic power actuator in a first part phase of its operation to move a said member to different of said positions, and means operable by said cyclic power actuator in a later phase of its operation to operate said escapement. Y

8. In combination with a typewriter having a letterfeeding carriage; an escapement mechanism operable to feed said carriage, means associated with said escapement mechanism to condition it for yield of carriage feeds of different magnitudes, said means including a member which is operable from a normal position to a plurality of different operated positions and which in each of said positions at operation of said escapement mechanism is adapted to control it to yield a different magnitude of carriage feed, a spacing key, a manual controlsettable to different positions representative of at least some of the carriage feeds for which the escapement mechanism is conditionable, a part controlled for operation in different paths by different settings given to said manual control, stepped faces on said part, means uni formly limiting the extent of operation of said part,

means engageable by the different faces of said partin dependence of the pathof movement of said part to move said member at least to some of said different positions, a cyclic power actuator adapted to be called into operation by said key, means to operate said part to its limit by said cyclic power actuator in a first part phase of operation of the latter and including a resilient motion transmitting element which flexes as said power actuator completes its cyclic motion, and means operable by said cyclic power actuatorin a late phase of its operation to operate said escapement mechanism.

9. In a typewriter having a selectively operable typing mechanism. and ,a carriage; the combination with an escapement which is capable of paying out to'the carriage feeds of different magnitudes, of means associated with said escapement and conditionable differentially to control it for paying out different magnitudes of feed to the carriage, means controlled by selective operations of said typing mechanism to exercise differentially control over saidconditionable means for the latter to govern automatically said escapement to pay out different magnitudes of feed to the carriage which are related to the widths of the individual characters that are being typed, a control operable to cause feeds of the carriage independently of said typing mechanism, means predeterm-inedly settable to denote different magnitudes of carriage feeds, but having normally no control over said conditionable means, and means to respond to said control and governed by the setting given to said settable means, to condition said conditionable means to control said escapement to pay out the particular magnitude of carriage feed which is denoted by the setting given to said settable means.

10. In a typewriter having a selectively operable typing mechanism and a carriage; the combination with an escapement which is capable of paying out to the carriage feeds of different magnitudes, of means associated with said escapement and conditionable differentially to control it for paying out different magnitudes of feed to the carriage, means to control said escapement by said typing mechanism to control the carriage for letter spacing, a control operable to cause feeds of the carriage independently of said typing mechanism, means predeterminedly settable to denote different magnitudes of carriage feeds, but having normally no control over said conditionable means, and means to respond to said control and governed by the setting given to said settable means, to condition said conditionable means to control said escapement to pay out the particular magnitude of carriage feed which is denoted by the setting given to said settable means.

11. In a typewriter having a selectively operable typing mechanism and a carriage; the combination with an escapement which is capable of paying out to the carriage feeds of regulated magnitudes, of means associated with said' escapement and differentially conditionable to regulate it for paying out different magnitudesof feed to the carriage, means controlled bythe selective operations of saidtyping mechanism to exercise differentially control over said conditionable means for the latter to regulate automatically said escapement to pay out different magnitudes of feed to the carriage which are related to the widths of the individual characters that are being typed, a control operable'to cause feeds of the carriage independently of the typing mechanism, means predeterminedly settable to denote different magnitudes of carriage feeds, but having normally no control over said conditionable means, and means responsive to said'control first to con dition said conditionable means in accord with the setting given said predeterminedly settable means and then to cause the operation of said escapement to pay out tothe carriage a feed of a magnitude in accord with the then conditioned conditionable means.

12. In a typewriter comprising a system of types, a letter-feed carriage, means constantly urging said carriage in letter-feed direction, elements arranged in a row and individually operable generally transversely of such row, and means operable by each of said elements to cause a typing impression by a related type, the combinationwith an escapement wheel which iscapable of rotation by the carriage in a carriage-advance direction, of an escapement dog, a stop against which said dog is normally engaged through carriage-advance rotation of said wheel, means operated automatically responsive to the operation of any of said elements to disengage said dog transitorily from said escapement wheel, spring. means to move said dog upon its disengagement in a direction from said stop, counter'to the said carriage-advance direction of rotation of said wheel, a rockable structure biased to normal position, being operable by specific ones of said elements to a short extent and being operable by specific ones of said elements to a greater extent, and being unaffected by operations of certain other elements, and a slide member operable from a normal position by said short and greater extent operations of said rockable structure, respectively to a first and to a second position, said slide member being configured to have in its normal position a face disposed to limit movement of the dog from said stop into a relation with said escapement wheel which will predetermine a reengagement herewithin a required tooth relation for controlling a two-toothadvance of the escapement wheel, said slide member being further configured to cause by its operations respectively to said first and said second position, movement restrictions of said dog from said stop which will respectively predetermine a reengagement with the escapement wheel in tooth relations therewith for controlling a three-tooth and a one-tooth advance of the escapement wheel.

13. In a typewriter comprising a system of types, a letter-feed carriage, means constantly urging said carriage in letter-feed direction, elements arranged in a row and individually operable generally transversely of such row, and means operable by each of said elements to cause a typing impression by a related type; the combination with an escapement wheel which is capable of rotation by the carriage in a carriage-advance direction, of an escapement dog, a stop against which said dog is normally engaged through carriage-advance rotation of said wheel, means operated automatically responsive to the'operation of any of said elements to disengage said dog transitorily from said escapement wheel, spring means to move said dog upon its disengagement in a direction from said stop, counter to the said carriage-advance direction of rotation of said wheel, a structure biased to a normal position, being operable by specific ones of said elements to one position and being operable by specific ones of said elements to another position, and being unaffected by operations of certain other of said elements, and a single member operable by said structure from a normalto either of two operated positions in deference of the operations of said structure to said different positions, said member being configured to have in its normalposition a face disposed to limit movement of the dog from said stop into a relation with said escapement wheel which will predetermine a reengagement therewith in a required relation for controlling a given multiple-tooth advance of the escapement Wheel, said member being further configured to cause by its operations to its two different positions, movement restrictions of said dog from said stop respectively into two differing relations with the escapement wheel predetermining respectively a reengagement therewith in required tooth relations for controlling-given tooth advances of the escapement wheel which compared to said given-multiple-tooth advance are respectively one tooth less and one tooth more.

References Cited in the file of this patent UNITED STATES PATENTS 727,553 Peterson May 5, 1903 2,167,812 Muller Aug. 1, 1939 2,225,356 Sibley Dec. 17, 1940 2,626,693 Henze et al Jan. 27, 1953 as... .agan 

